Auto Maker Investing Up to $185 Million in Tennessee Plant

General Motors Co. on Wednesday said it would invest as much as $185 million to build small engines at its Spring Hill, Tenn., factory and move production of its Cadillac SRX crossover vehicle to the facility from Mexico, capping a multiyear shift by the auto maker to bring more work back into its unionized U.S. factories.

Production of the about $40,000 SRX, now assembled at the Detroit auto maker's Ramos Arizpe, Mexico, factory,...